This invention refers to a cellular depot comprising innovative cars or transelevators for moving loads, for example containers, to and from the cells.
There are known depots composed of a reticulated structure forming a plurality of cells disposed side by side in rows on several floors. The cells face, with an aperture for inserting and removing, onto a corridor along which the conveyor cars run.
As a rule, the cars run along rails parallel to the rows of cells and carry telescopic forks or movable platforms which are motor-driven to enter the cells and withdraw or deposit the load.
In the case of very large loads, such as for example containers, motor vehicle bodies, tube nests, etc., the forks or platforms have to carry out a very long stroke to insert themselves completely into the cells.
As the stroke increases, the problems deriving from clearances, elasticity and overall dimensions of the telescopic parts increase until such solutions rapidly become technically and economically disadvantageous. Cellular depots have been proposed, in which the transelevators or cars comprise guides which couple with guides provided in each cell, to enable an electric motor-driven trolley to transfer the loads between the transelevator and the cell.
In order to provide power to the trolley,. complicated movable electrical connections have been proposed, such as rigid conductors with sliding shoes, cables with winding drum, flexible track elements, etc. Such connections are sources of problems and intense maintenance due to the large number of handling cycles that the trolleys carry out. In addition, they often call for excessively large volumes of space.
It has also been proposed to use batteries to supply power to the trolley, to render it independent. To avoid the periodical stoppages of the system for recharging the accumulators, depots have been proposed in which, when the trolley is completely accommodated on the car, the electric accumulator is connected, for recharging, by means of an automatic electric coupling, to a source of power reaching the car.
The use of electric accumulators, which although offering advantages as compared to the use of permanent electric connections between the car and the trolley, lead to other problems of a practical nature. In fact, it is necessary to carry out a periodical check of the accumulators and the recharging systems, the accumulators must be replaced at the end of their life cycle, precautions must be taken against the risk of emission of gas when recharging and the loss of highly corrosive liquid (which, moreover, is in any case always potentially dangerous to handle during maintenance operations). In addition, the system is relatively sensitive to jolting and vibrations, which are inevitable during operation.
It must also be considered that the electric accumulators suffer a shortening of their average lifespan whenever they are subjected to brief and frequent running down and recharging cycles, and that the temperatures in the depots (for example refrigerated) may be outside the normal values for operation of the accumulators. Lastly, the electric accumulators are of standardized dimensions which make it necessary to adapt the dimensions of the trolley to the accumulators, resulting in considerable thickness of the trolley and a loss of useful space within the cells.
The general scope of this invention is to obviate the aforementioned problems by providing a cellular depot system in which the cars comprise transfer trolleys which are independent, enable the intensive and continuous use of the system, are sturdy and reliable, and have limited overall dimensions and low manufacturing and maintenance costs.